J01N£ OF AGRICTOAL RESEARCH 



Vol. XVIII Washington, D. C, January 2, 1920 No. 7 



EFFECT OF LIME UPON THE SODIUM-CHLORID TOLER- 

 ANCE OF WHEAT SEEDLINGS 



By J. A. LE ClERC, Chemist in Charge, Plant Chemical Laboratory, Bureau of Chemistry, 

 and J. F. BrEazealE, Associate Biochemist, Bureau of Plant Industry, United States 

 Department of Agriculture * 



INTRODUCTION 



The work reported here is a continuation of that previously reported 

 in Bulletin 149 of the Bureau of Chemistry. In this former work the 

 beneficial effect of lime upon soils which have become acid by the con- 

 tinued use of potassium chlorid or potassium sulphate was pointed out. 

 The present work takes up an equally important role of lime — its effect 

 upon some of the salts commonly occurring in "alkali " soils. 



The concentration of nutrient salts best suited to plant growth ^ is en- 

 tirely different in sand and in solution cultures. Seedlings grown in 

 a solution of 2,500 parts per million of nutrient salts suffer, while those 

 grown in sand and watered continuously with the solution, with free 

 drainage, produce vigorous plants. From this it appears that inert 

 material, such as sand, clay, and soil, might materially affect the toxic 

 limit of dissolved salts. It was, therefore, desired to see whether a plant 

 growing in a stiff soil would be more resistant to sodium chlorid, which 

 is one of the salts found in alkali soils, than one growing in a sandy soil 

 or in a solution. 



EXPERIMENTS 



SERIES I 



Several small glass jars having a capacity of 250 cc. were filled with 

 sodium-chlorid solutions of the following concentrations: 



SOLUTION NO. CONCENTRATION OP SOLUTION. 



1 Distilled water. 



2 500 parts per million of sodium chlorid. 



3 1,000 parts per million of sodium chlorid. 



4 2,000 parts per million of sodium chlorid. 



5 3,000 parts per million of sodium chlorid. 



6 4,000 parts per million of sodium chlorid. 



1 Much appreciation on the part of the authors is due to Dr. J. Davidson for his painstaking review and 

 correction of the manuscript. 



' BrEAZEALE, J. F. EFFECT OP THE CONCENTRATION OF THE NUTRIENT SOLXmON UPON WHEAT CULTURES. 

 In Science, v. 22, no. 553, p. 146-149. 1905. 



Journal of Agricultural Research, Vol. XVIH, No. 7 



Washinsrton, D. C. ' Jan. 2, 1920 



tg (347) Key No. E-12 



